SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '64f8145d74666e075082087c3bb9bb5699539458463b75d0972c4e616ad9dbcc' 
  AND token = 'H3XrLPTe/PwzEKZvwcgtFTnE3cfgqcB0voEZMPtGjB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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