SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ad9f64e790d1bb82d7e2c0021e44910018ec80f1f8de2e44cc56e7c94a7bcc0' 
  AND token = 'V7PCUmj05rLBrT8cq1xsCf8h34s0TLvmQ15Cm4D/LBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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