SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ffe7e3fb0f70d47faf10cd113dc5da2e7e67b00966dd36fe34a4ecd7cb636ef' 
  AND token = 'vBh4MsOJDQ983QRhiXWs7pugVmgsj1R1e7Wd248d+pA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables