SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbef24e7cbd804418d4c033cd060225d2dd7a5c0b595191da8b6f1d80d0ac6e5' 
  AND token = 'cHJezwxSGhQ1eqdkvgPii0Y9egfWu0uRpKh0zVYvn1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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