SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cacb6dd5b58d9d4b9b1dce1c53e2e85ebfc0c9e83e827da74823b61334c4abc2' 
  AND token = 'yRg7p7jpLSPtenoMoa66AqToLVfOcDgNxGySEibdVDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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