SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c34de7ad64427cf8012519754f37f1d92728aba225e6e83f576d69c39c2c8e7' 
  AND token = 'kZQxoI6soJWSi/t6s3jStnX+8GpBOw3CXBvYB9S+DIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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