SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b48d8d1a5b7745ae51cc417a81f9e51972e8bf6e12369fc0d2cd062f843c260' 
  AND token = 'Wi8Ic3uzRlCUiupxtCpb8F4vV3Vj5W3+ziaCGPfuzPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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