SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a699c95d7fa132ede959867f3c45165782aa69deae12f19188184e8eba3888bc' 
  AND token = 'I2+bxqtT8cmr9GsKIzNSGfb+Yvo9CklIdV+DX88PH3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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