SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2efaa38df276e2244d9806f392ccd0f9e270e2cfc17c0469abb0dd16b8d8bb1f' 
  AND token = 'TPkpWA5OPakyYt9SjkWJOxN47sehsHVYn43yGVomtSM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}