Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe30fbfc70c4e3eea860a67164d432be0890e2dddf6c6befc8f78ee7a7bb1900' 
  AND token = 'PDHEidQmS29bvPqJ9kJ2mDFlSaGCn2R6LpBDeCGpqCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}