SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e68f16edd8c18a6eaafab5836644ecf4d005929b1f913cab73decea33be1370e' 
  AND token = 'tGYfROVAFzP9pf7E8nJKxa5XdrGHzD2PMKsYpZJciDY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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