SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e54b66743944864d4972792d2891c8587eff8fe2310480f0c7bcd9855eeed454' 
  AND token = 'tCMm8sGcMuBTuR0tX8qB4QsirpNqzw3kUFvjJNp5c1M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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