SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf6eb414066c963fb57243b2d945e4fed07f3641553cb738b1a5940d4212fd2e' 
  AND token = 'XvAzJNxOa9SUrolIltlpnSct/NguSh3OepZ3GWLabmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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