SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2208d79f9556c99463bf63ca85261f2aac4151d82f49aabdf0de79f5ded960c' 
  AND token = 'jedFjO5E3b97gLuxrpQosCp2bWqBW8AQSg5ZjNmYnBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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